You can map a curve onto a surface using a transfer feature.
Important:
When mapping other geometry than concept surfaces, you must first create a transfer feature from the points associated with the geometry to be mapped. The Transfer Feature command is available in the points context toolbar.
Before you begin: Open a 3D Shape containing a curve and a surface.
Select an end point of a curve to be mapped.
From the context toolbar, click Create a Transfer Feature.
A Transfer.x feature is added to the tree.
Create another transfer feature from the other curve end point.
Select the curve and from the context toolbar, click Map.
In the Map Targets section, click Modify Map
Target.
Select a surface as map target and click Select map targets.
The curve is mapped onto the surface. An arrow indicates the map
direction.
command is available in the points 
.
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